Door-key retainer



7 March 20, 1928. 1,663,354

A. SMITH DOOR KEY RETAINER Filed Jan.l2. 1927 Patented Mar. 20, 1928.

U NIIE STATES;

.ALLIE SMITH, or MINNEAPOLIS, MINNESOTA.

DOOR-KEY RETAINER.

Application filed January 12, 1927. Serial No. 160,586.

I This invention relates to key retainers, and'has for its main objectto provide a simpic but highly eflicient device adapted to be carried byor attached to an ordinary key,

whereby in co-operation with the key hole of adoor, said key will beprevented from being surreptitiously removed from the opposite side. ofthe door;

key hole extending therethrough, it is a comparati'vely simple expedientto manipulate and turn an inside key-in the lock from the outside of thedoor by means of a similar key or skeleton key and to force the insidekey out of the lock after alining the same with the key hole. My deviceprovides simple means whereby the inside key is prevented from turningin the lock and consequently from removal therefrom.

A more specific object of the invention is to provide a wedge memberadapted to engage the inside plate of the door about the key hole, saidwedge member being connected with the handle portion of the key toprevent oscillation of said key in the lock, simple means being providedfor quickly setting the device in working position and withdrawing thesame for removal of the key.

These and other objects of the invention 30 will be apparent from thefollowing description made in connection with the accompanying drawingwherein like reference characters refer to similar parts throughout theseveral views, and in which:

Fig.1 is an elevation of the free edge of a door provided with the usualtype of lock and having a preferred embodiment of my invention appliedthereto;

Fig. 2 is a plan view of my device carried by a door key; and

Fig. 8 is a vertical section taken on the line 3-3 of Fig. 1. I

In the drawings, a portion of a door 4 is illustrated having mountedthereon the usual lock indicated as an entirety by the numeral 5, thelatch of which is controlled by the knob, 6. The usual door plate 7 inwhich the knob is journaled is secured to the inner surface of the doorbeing provided with the key hole 8, communicating with the lockingmechanism. The skeleton key 9, of usual type is shown having thefiatannular handle 9. f r

In Fig. 1 the key 9 is shown inserted in the door lock and turned tosubstantially horizontal position, in which withdrawal from the lock isimpossible. p

I provide a wedge shape or frusto-conical plug 10 carried at one end ofa square rod or plunger 11, and rigidly connected thereto. Rod 11 isslidably journaled in a strap or frame 12, which is preferably formedfrom a flat stripof material, shaped to aflord'a In the ordinary type ofdoor having the pair of oppositely disposed ears 12 having alined squareapertures therein to receive rod 11. The strap 12 alsoincludesaresilient hook portion 13adapted to engage a portion of the key handle9. Strap l2 is preferably made of a stri of material of sufficient widthto permit of little turning of said strap relatively to the key handle 9when attached thereto.

The strap 12 is secured to the rod 11 in any suitable manner, such as bya coiled or split ring lt passing through a small transverse hole in theouter end of rod 11, and a coiled compression spring 15 is interposedbetween the inner ear 12 of strap 12 and the plug or head 10.

As seen in Fig. 8, the key engaging surface of the plug 10 is preferablyconcave to substantially conform to the shaft of the key.

In operation, the hook 13 is first secured to the handle 9 and the keyinserted in the door and the door locked. The key is then turned tosubstantially horizontal position, whereupon the ring 14. may bemanipulated to move plug 10 in the direction of strap 12 against thetension of spring 15. The extremity of plug 10 may then be inserted inthe circular portion of the key hole in plate 7 above the shaft of thekey and the ring 14 released. Compression spring 15 will yieldinglyforce plug 10 into the key hole, so that it will be practicallyimpossible to move the plug from the opppo'site side of the door. Theconnection between strap 12 and the annular handle of the key.positively prevents oscillation of the key relatively to the plug 10 andplunger 11.

Since it is impossible to exert any substantial amount of leverage onthe key from the outer side of the door, my devicewill rendersurreptitious entry of the door impracticable.

It will be seen that my device is simple in nature, capable ofmanufacture at exceedingly low cost, and can be carried by the key atall times conveniently as a key ring, which may be easily supported on ahook or nail when the key is not in use. The strap 12 may be quicklyattached to the key handle 9 due to the resilient nature of hook portionoscillation in the round part of a key hole against the shaft of a key,a plunger carried by said tapered member and axially alined therewith, aconnection member in which said plunger is slidably mounted but heldagainst oscillation, an elastic element interposed between said taperedmember and said connection member, a stop disposed adjacent the rear endof said plunger to limit-the slidable movement of said plunger insaidconnection member, said connection member having a substantially flathook adapted to pass through the annular handle of a key to hold saidkey against oscillation in the door lock.

2. A door key retainer comprising a tapered member adapted to be seatedagainst oscillation on the round part of a key hole against the shaft ofa key, a plunger of rectangular cross section carried by said taperedmember and axially alined therewith, a U-shaped member having oppositelyalined rectangularapertures in which said plunger is slidably mounted, acoiled spring surrounding said plunger and interposed between saidtapered member and said U- shaped member, a handle disposed adjacent therear extremity of said plunger adapted to limit the forward movement ofsaid plunger in said U-shaped member, said U-shaped member also carryinga substantially flat resilient hook adapted to pass through the annularhandle of a key to retain the same against oscillation.

In testimony whereof I affix my signature.

. ALLIE SMITH.

